WASHINGTON (Reuters) - Democratic presidential nominee Joe Biden tested negative again for COVID-19 on Sunday in a polymerase chain reaction (PCR) test, his campaign said, according to a press pool report. Biden, who shared a debate stage with President Donald Trump last Tuesday in Cleveland, also had tested negative in two tests on Friday, the day Trump disclosed his coronavirus infection. The campaign gave no other details when asked about the frequency of Biden’s recent testing, according to the pool report.